The present invention generally relates to wireless telecommunication systems. More particularly, the present invention relates to methods and devices which enable group communication, such as “Push-To-Talk” (PTT) communication, without requiring dedicated PTT hardware.
In wireless telecommunication devices, such as cellular phones, PDAs, mini-laptops, and advanced pagers, the devices typically communicate over long distances by bridging telephone calls through existing cellular telephone networks and passing data packets across the network. These wireless communication devices often have data processing and computing capabilities, and can accordingly send and receive voice and other types of data across the telephone network.
There exists a wireless telecommunication service that provides a quick one-to-one or one-to-many communication that is generically referred to as “Push-To-Talk” (PTT) capability. The specific PTT group of recipient devices for the communicating wireless communication device is commonly set up by the carrier. A PTT communication connection is typically initiated by a single hardware button-push on the wireless communication device that activates a half-duplex link between the speaker and each member device of the group and once the button is released, the device can receive incoming PTT transmissions. Existing PTT systems have advantages over traditional cellular systems because they have faster call setup times, e.g., setup times ideally in the range of 1 second as opposed to cellular voice channels that can take more than 5 seconds to establish. In some arrangements, the PTT speaker will have the “floor” where no other group member can speak while the speaker is speaking. Once the speaker releases the PTT button, any other individual member of the group can engage his or her PTT button and he or she will have the floor. Generally speaking, the PTT system uses standard voice-over Internet protocol (VoIP) technologies. Voice information is sent in digital form over IP-based data networks. In PTT scenarios, instead of using the standard cellular infrastructure a call is formed by combining separate point-to-point connections between each IP endpoint in the network. Initiating the PTT system generates a call to the target device. The call originator's voice can be sent through the carrier's network to the target handset.
A drawback to existing PTT services is that they typically require devices with dedicated PTT hardware components, such as a hardware PTT button, meaning that these services are generally not available for the majority of mobile devices in use today.